1. Field of the Invention
This invention relates to barge haulage systems and to the art of moving non-self-propelled barges in a channel or alongside of a pier, particularly when unloading of a bulk material carried within the barge is to be accomplished and both forward and backward motion of the barge is required during several passes of the barge by the unloading device.
2. Description of the Prior Art
Barge haul systems using one or more powered winches and wire ropes reeved from the drums of the winches around suitably located sheaves to each end of the barge so that reversible movement of the barge may be obtained are old in the art. Such rope operated barge haul systems are disclosed in U.S. Pat. Nos. 2,773,608 to R. E. HUNT et al; 3,104,766 to J. SASADI; 3,307,717 to C. LUDWIG and 3,497,054 to J. P. VAN KLEUNEN.
The use of tugs for moving barges within the unloading area is also old, but it is generally preferred to maintain control of the barges from within the operator's control station of the unloading device.
In U.S. Pat. No. 3,362,546 to D. B. SALE a barge unloading device is disclosed wherein angularly positioned rubber tired wheels attached to the movable unloader carriage make contact with a rail on each longitudinal side of the top of the barge to guide the barge as it is moved through the area of the unloader and to index the unloader with respect to the bottom of the barge. This patent further discloses that the indexing wheels may be power driven to urge the barge longitudinally through the truss of the unloading device.